1. Field of the Invention
This invention pertains generally to electrical communications, and more specifically to vehicle position indicators that signal a vehicle's anticipated arrival. In one more specific manifestation, the indicators are for school buses or other similar public transportation, though other manifestations are also described.
2. Description of the Related Art
Many different modes of transportation exist that utilize an operator, such as a driver, engineer or other ones of the myriad of names provided for such persons, and a vehicle to transport one or more passengers from one location to another. Operator-controlled transportation brings many universally recognized benefits. Among them are the conservation of energy, which is particularly beneficial in such instances as buses, light and heavy rail and the like. These mass transit systems also preserve real-estate by carrying many passengers in a single line in an efficient manner, while not requiring any associated automobile parking space. Where parking may be limited or completely unavailable, such as is common in larger cities or in special locations or facilities, such types of transportation may be the only viable mode of travel. Finally, in the cases of more private methods such as taxi cabs and the like, transportation is frequently made available where it would have otherwise not been possible or practical.
Nevertheless, operator-controlled transportation has, in many cases, garnered a reputation as eing somewhat less convenient than personal transportation for most ordinary trips. This is because the passenger must be at a pick-up location and ready for boarding well in advance of the anticipated arrival of the vehicle. This adds additional time to the trip, and also exposes the passenger to the vagaries of the environment. Such early arrival is necessitated since many of these vehicles will have a slightly variable arrival and departure time, and these vehicles will preferably not wait at any stops. Waiting at a stop would undesirably prolong the trip made by the vehicle, which would only add to the travel time and consequent inconvenience of this type of transportation for all passengers. Furthermore, the additional time to travel a route will also necessitates additional billing to compensate the operator, and reduce the availability of the vehicle for covering either the same or other routes. This is particularly true in the instance of more private modes of transportation, such as taxi cabs or the like, where wait times may be directly billed to the passenger.
Beyond inconvenience and minor added expense, and for many passengers an issue of greatest paramount, is the issue of safety. There are many locations where public transportation must be provided but cannot economically be provided with adequate security to ensure the safety of all passengers. One particular instance is the bus stop, which often serves as the gathering point for many diverse persons. All too often, these persons are for one reason or another more vulnerable than most. One particular instance is that of a school bus stop, where very young or small children must gather and wait for the school bus or where they will be dropped a the end of the school day. Unfortunately, these bus stops are scattered all about the country-side, from street corners to rural locations. Since the only persons traveling are school aged children, and since in many school districts transportation may be provided at different times for different age groups, it is entirely possible for kindergarten or elementary school children to be the only passengers at a stop. Further compounding the matter, at some times of the year and in some localities, the pick-up or drop-off times will be outside of daylight. While many times it is possible for the districts to avoid such scheduling, there are still some instances where this occurs. During these times, the young children are very vulnerable. Even with adults, a single or few passengers may be vulnerable and consequently unsafe.
In order to improve the safety and convenience of operator-controlled transportation systems, a number of systems have been developed which notify a passenger of an impending arrival of a vehicle. These systems are desirable since the transit time may be reduced, by reducing the amount of waiting at a pick-up or vehicle stop. Safety is improved, since the passenger is exposed for less time, and the vagaries of the environment, such as rain or the like, are somewhat less consequential. Where an individual will be picked up at their residence, or nearby, such systems provide ample advance notice for the passenger to be ready just as the vehicle arrives. This improves the efficiency and safety of the transit system for all.
Exemplary of the prior art systems, and each incorporated herein by reference for their specific teachings, are U.S. Pat. No. 5,021,780 to Fabiano et al; U.S. Pat. No. 4,325,057 to Bishop; U.S. Pat. No. 4,297,672 to Fruchey et al; U.S. Pat. No. 4,713,661 to Boone et al; U.S. Pat. No. 6,191,708 to Davidson; U.S. Pat. No. 4,350,969 to Greer; U.S. Pat. No. 5,144,301 to Jackson et al; U.S. Pat. No. 5,400,020 to Jones et al; U.S. Pat. No. 5,680,119 to Magliari et al; and U.S. Pat. No. 6,184,802 to Lamb. The patents of the prior art may somewhat generally be grouped according to the techniques which are provided to enable advance notice. One approach, illustrated by Jackson et al, is to use a low-power transmitter which triggers an audible or visual signal when close enough to a receiver. This technique requires very little capital cost, and may therefore be implemented readily by many transit systems and providers. However, there are few available unique frequencies in the radio spectrum, and interfering signals can cause the receiver to falsely trigger. In areas where several transportation vehicles will simultaneously operate, it can be extremely difficult to avoid triggering from the wrong vehicle. Such false alerts render the system relatively ineffective for all but the most rural of routes.
One approach which avoids the false triggering is illustrated, for exemplary purposes, by Jones et al. Using this system, a transportation vehicle is provided with relatively advanced electronics that may, for example, employ position detection systems such as GPS, Loran or the like, together with various sensors to detect the status of the transit vehicle. The transit vehicle may then be monitored for movement, and an arrival schedule predicted with some reliability. Passengers then subscribe to the system provider, who may use an automated dialing system with unique ring to notify the passengers at the appropriate time that the transit vehicle is approaching. For systems with fewer subscribers, this type of system offers several advantages. First of all, the location and status of each transit vehicle may be monitored very accurately. The relatively high capital cost of the equipment is limited to the transit vehicles, and not further multiplied by any passenger equipment. Unfortunately, when volumes of passengers increase, the amount of time required for timely notification also increases. Said another way, while everything is conveniently centralized, the load upon the central system may increase to a level which is greater than that which may be managed. Consequently, as the numbers of subscribing passengers increase, the system becomes substantially more expensive and more difficult to operate and maintain.
In all of these prior art systems, there is little in the way of flexibility provided to the subscriber, beyond how much advance notice the subscriber wishes to receive. Consequently, these systems are optimized for mass transit systems which are simply announcing the anticipated arrival of the transit vehicle at a particular stop.